1. Field of the Invention
The present invention relates generally to the field of medical systems, and more specifically to managing connection establishment processing for wireless devices.
2. Description of the Related Art
Traditionally, medical system products transmit control signals over a fixed wire or cable using a standard cable interface, such as USB, Ethernet, etc. Current advancements in wireless communications techniques, including short-range radio and light wave technology, enable designers to employ wireless connections to transmit control signals and other data, thus removing the need for a traditional fixed wire or cable. Examples of removable or non-fixed devices include monitors or monitoring equipment, test equipment, remote control devices, and so forth.
The rapid advancement and proliferation of short-range radio technology affords medical system product designers and manufacturers the ability to create and deploy non-fixed subsystems and devices without need for a conventional fixed physical communication cable. For example, non-fixed devices meeting or complying with the Institute of Electrical and Electronics Engineers (IEEE) 802.11g, IEEE 802.15.4 standard (ZigBee), and Ericsson Bluetooth™, referred to herein simply as “Bluetooth,” specifications provide short-range radio technology to enable for wireless communications. These technologies allow for wireless transmission of signals over short distances between computers and other electronic devices. Bluetooth enabled devices are capable of an approximate 10-meter transmission range at data rates up to 720 kilobits/sec, and can provide better security features than devices implementing IEEE 802.11g communications.
Although typically not well suited for medical applications, line-of-sight wireless light wave technology, including Infrared Data Association (IrDA) techniques, may also be employed by product designers to realize wireless connections.
Implementing either the Bluetooth or IEEE 802.11g specifications will yield a communications path between wireless non-fixed devices and subsystems. Each specification also addresses providing an interference resistant communications path with automatic error detection and correction capabilities for transmitting and receiving of control signals, data, and information.
In summary, Bluetooth technology enables communication between two wireless devices without use of a fixed cable connection. Bluetooth, ZigBee, and IEEE 802.11g specifications address the establishment of a communications path to form a wireless connection for the transmission and reception of data, control signals and information across a single communications path.
Bluetooth and ZigBee implementations employ a bonding process to establish a new relationship between two Bluetooth enabled devices before they can exchange data. In this context, bonding refers to a mechanism where the two devices are exchanging protected passkeys and form a link. Once bonded, all data and information transmitted over a Bluetooth, ZigBee, or similar link is encrypted and only those slave devices authorized during the bonding process will be able to receive and decipher this encrypted transmission.
In a mass production environment, each slave device of a Bluetooth or similar system requires bonding with a master device in order to perform various quality control tests and safety checks in accordance with Food and Drug Administration and other functional and business requirements. Problems arise in a mass production environment where the potential number of slave devices that may be found available during the searching phase becomes quite large. The searching process associated with master-slave device bonding process may return a long list of addresses in this environment and may easily exceed the search limit defined by the protocol (in the case of Bluetooth, currently 7-9 devices, depending on implementation).
Due to this limitation, the list of addresses may fill up rapidly and thus prevent the desired or intended slave devices from being entered into the list. A manual process of entering the slave device address into the host system in order to bond the devices may replace the searching phase. Today's mass production environments require increasing manual intervention in proportion to factory floor production yield rates to coordinate and manage quality control tests and safety checks. Manual intervention consumes large amounts of time in order to successfully pair all wireless slave devices to a master device and is prone to human errors.
In an operating theater environment, safety issues may arise if the searching process acquires addresses from slave devices already in use. For example, if a non-fixed wireless medical subsystem of device is required to perform a surgical task, it must be first bonded with a instrument host. When the instrument host initiates the bonding process for the non-fixed wireless medical device, the instrument host instructs the master device to search for all slave devices within range. This may become problematic if this search includes slave devices that are within range and currently in-use in an adjacent operating room. Moreover, if the master device successfully bonds with a slave device in a different operating room, not only may this pose a safety hazard, but at a minimum will consumes a great deal of time to eliminate this error. If an enabled slave device requires replacement during an operation, an efficient and reliable bonding process is paramount to continuing the procedure while minimizing disruption.
Mass production environments and surgical operating rooms employing non-fixed wireless medical subsystems and devices require an efficient, accurate and reliable method for searching and pairing a master and slave device to facilitate efficient operation of the mass production line and ensure safety in the operating environment.
Thus it would be advantageous to offer an architecture and design that provide wireless operated subsystems and devices a reliable and accurate connection management scheme to rapidly bond devices.